Illumina reached an intraday high of $77.11, $9.95 higher than its Thursday close of $67.16. Since Illumina has a market cap of more than $8.5 billion -- the largest of any biotech company in San Diego County -- that's a considerable movement. Shares closed at $69.98, up $2.82 for the day.

Last year, Illumina was an acquisition target of Swiss drug giant Roche, but rejected the offer as undervaluing the company. As late as December, reports said a deal might be in the works, but Roche has said its offer has been withdrawn.